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FAIR VALUE MEASUREMENTS (Details 2) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Cash equivalents and marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | $ 41,007 |
Less Than 12 Months - Gross Unrealized Losses | (19) |
Total - Estimated Fair Value | 41,007 |
Total - Gross Unrealized Losses | (19) |
Government-sponsored enterprise securities (due in less than one year) |  |
Cash equivalents and marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | 3,947 |
Less Than 12 Months - Gross Unrealized Losses | (1) |
Total - Estimated Fair Value | 3,947 |
Total - Gross Unrealized Losses | (1) |
Corporate notes (due in less than one year) |  |
Cash equivalents and marketable securities with unrealized losses |  |
Less Than 12 Months - Estimated Fair Value | 37,060 | 27,045
Less Than 12 Months - Gross Unrealized Losses | (18) | (8)
Total - Estimated Fair Value | 37,060 | 27,045
Total - Gross Unrealized Losses | $ (18) | $ (8)

X
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- Definition Amount of gross unrealized loss on securities classified as available-for-sale securities that have been in a loss position for less than twelve months as of the reporting date. + References No definition available. + Details
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